Noticed last year before I tore my FXR down the speedo doesn't work. The cable end (flat end) is too small for the speedo and when the cable turns it just spins. Do they make different cable ends for different ratios? I have never paid attention.

 

I've never noticed any difference in the size of the internal cable other than length. But then I havent seen every available speedo cable either so I could be wrong. Usually the only other difference is the size of the knurled nut to secure it to the speedo. You might try calling J&P technical assistance and see what they say. That's if your local Indy or dealer cant help.
Sorry, I'm no more help!
jim

 

I haven't come acrosss different cables. What year is your bike? We can supply correct part numbers between us!

 

88 FXR but on a custom frame. The nut and speedo are correct, just the flat end of the cable is smaller than the slot in the speedo. When the cable turns it doesn't drive the speedo, so it reads 0 all the time.

 

Assuming the outer cable is the correct one all you need is a replacement inner if they are still available separately. J&P have replacements cable assemblies.